Boxer membrane pump



FIG. 1 is a top, left, front perspective view of a boxer membrane pump in accordance with our new design in which the broken lines do not form part of the claimed design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a front elevational view thereof;

FIG. 6 is a rear elevational view thereof; and,

FIG. 7 is a right side elevational view thereof. 

The ornamental design for a boxer membrane pump, as shown and described. 